[Show abstract][Hide abstract] ABSTRACT: Background:
Schistosomiasis remains a major public health problem in China. The major endemic areas are located in the lake and marshland regions of southern China, particularly in areas along the middle and low reach of the Yangtze River. Spatial analytical techniques are often used in epidemiology to identify spatial clusters in disease regions. This study assesses the spatial distribution of schistosomiasis and explores high-risk regions in Hubei Province, China to provide guidance on schistosomiasis control in marshland regions.
In this study, spatial autocorrelation methodologies, including global Moran's I and local Getis-Ord statistics, were utilized to describe and map spatial clusters and areas where human Schistosoma japonicum infection is prevalent at the county level in Hubei province. In addition, linear logistic regression model was used to determine the characteristics of spatial autocorrelation with time.
The infection rates of S. japonicum decreased from 2009 to 2013. The global autocorrelation analysis results on the infection rate of S. japonicum for five years showed statistical significance (Moran's I > 0, P < 0.01), which suggested that spatial clusters were present in the distribution of S. japonicum infection from 2009 to 2013. Local autocorrelation analysis results showed that the number of highly aggregated areas ranged from eight to eleven within the five-year analysis period. The highly aggregated areas were mainly distributed in eight counties.
The spatial distribution of human S. japonicum infections did not exhibit a temporal change at the county level in Hubei Province. The risk factors that influence human S. japonicum transmission may not have changed after achieving the national criterion of infection control. The findings indicated that spatial-temporal surveillance of S. japonicum transmission plays a significant role on schistosomiasis control. Timely and integrated prevention should be continued, especially in the Yangtze River Basin of Jianghan Plain area.
PLoS ONE 04/2015; 10(4):e0118362. DOI:10.1371/journal.pone.0118362 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To investigate the effect and current situation of the standardized construction of laboratories of schis- tosomiasis control institutions in Hubei Province, so as to provide the evidence for establishing and improving the quality control system of diagnosis of schistosomiasis after the transmission of schistosomiasis was under control.
According to the procedures of self-examination, field operation, and laboratory on-site, five laboratories were assessed, and all the results were analyzed comparatively.
The average number of staffs were (7.00±1.58) persons, and the staffs of the laboratories of the schistosomiasis control institutions with senior professional titles in the city level were more than that in the county level (t = 5.563, P < 0.05). The average space was (3.20±1.64) rooms, and the average area was (117.00±88.29) m2. The average score of field operation was (96.40±4.49) points. The average score of laboratory on-site assessment was (106.6±6.15) points. The highest and lowest of the laboratory on-site assessment scores were environment and facilities (19.60 ± 0.55) points and management system of laboratory quality control (15.70±2.39) points (F = 2.869, P < 0.05), respectively.
The cultivation of laboratory staff should be strengthened, and the diagnostic capacity should be maintained and improved. The laboratory quality control system should be paid more attention to, and the construction and management of schistosomiasis laboratories should be standardized.
Chinese Journal of Schistosomiasis Control 02/2015; 27(1):22-5.
[Show abstract][Hide abstract] ABSTRACT: Objective:
To assess the schistosomiasis endemic situation in the national surveillance sites in Hubei Province, so as to provide the evidence for the prevention and control of schistosomiasis.
According to the national surveillance protocol, a longitudinal surveillance of endemic situation of schistosomiasis was carried out in 16 national surveillance sites from 2005 to 2010.
In general, the positive rates of IHA, Kato-Katz technique and infection rates of Schistosoma japonicum decreased from 15.67%, 10.93% and 1.71% in 2005 to 10.48%, 8.54% and 0.90% in 2010, and declined by 33.12%, 22.70% and 47.95%, respectively. The infection rates of S. japonicum of the male were higher than that of the female, and the peak infection rates were in the groups aged above 30 years. The endemic situation of fishermen and farmers were relatively serious. The infection rates of S. japonicum in cattle decreased from 11.69% in 2005 to 1.41% in 2010, and declined by 88.01% (χ2 = 298.79, P < 0.001). The areas with infected Oncomelania hupensis snails, the densities of living snails, the rates of infected snails and the densities of infected snails decreased by 90.88%, 61.66%, 80.00% and 92.00%, respectively.
The schistosomiasis endemic situation in the national surveillance sites in Hubei Province mitigates in 6 years, but the prevention is still a very daunting task.
Chinese Journal of Schistosomiasis Control 06/2014; 26(3):260-4.
[Show abstract][Hide abstract] ABSTRACT: Objective:
To analyze the progress of implementation of integrated strategy with emphasis on the control of infectious sources and effectiveness for joint-project of schistosomiasis control in Hubei province.
Data on the endemic status and implementation of each integrated intervention in 6 collaborated counties including Gongan, Hanchuan, Honghu, Jiangling, Xiantao and Yangxin during 2009-2013 were collected and analyzed. 18 administrative villages with a history of endemic schistosomisis from 6 counties were selected for field survey. Individuals aged 6-65 years received screening test by IHA, and feces of antibody positive inhabitants were collected and tested by miracidia hatching technique. Hatching technique was conducted to determine the infection rate of schistosomiasis in cattle if there was any cattle existed.
Various interventions were conducted with adaption to the local situation by the Departments of Agriculture, Water Conservancy, Forestry, and Health. The total number of cattle decreased from 75 388 at the beginning of 2009 to 1 805 at the end of 2013 in 6 counties with a reduction rate of 97.5%, while the prevalence in cattle reduced to 0-0.3% in 2013. Snail-infested areas were stable but areas with infected snails decreased significantly, and no infected snails were found in 2012-2013. Meanwhile, the infection rate of human beings on county level were less than 1%. No infected snails and cattle were found in 18 selected villages and the prevalence in inhabitants was in the range of 0-0.8%.
Cooperation between provincial government and the Ministries of Health and Agruiculture accelerates the process to reach the criteria of transmission control of schistosomiasis in Hubei Province. However, sustainable effort in needed as the current endemic situation of schistosomiasis is stillunstable.
Zhongguo ji sheng chong xue yu ji sheng chong bing za zhi = Chinese journal of parasitology & parasitic diseases 06/2014; 32(3):180-5.
[Show abstract][Hide abstract] ABSTRACT: Schistosomiasis remains a major public health problem in China. The major endemic foci are the lake and marshland regions of southern China, particularly the regions along the middle and lower reach of the Yangtze River in four provinces (Hubei, Hunan, Jiangxi, and Anhui). The purpose of our study is to assess the effect of a new integrated strategy emphasizing infection source control to curb schistosomiasis in marshland regions.
In a longitudinal study, we implemented an integrated control strategy emphasizing infection source control in 16 villages from 2005 through 2012 in marshland regions of Hubei province. The interventions included removing cattle from snail-infested grasslands, providing farmers with mechanized farm equipment, improving sanitation by supplying tap water, building lavatories and latrines, praziquantel chemotherapy, controlling snails, and environmental modification.
Following the integrated control strategy designed to reduce the role of bovines and humans as sources of Schistosoma japonicum infection, the prevalence of human S. japonicum infection declined from 1.7% in 2005 to 0.4% in 2012 (P<0.001). Reductions were also observed in both sexes, across all age groups, and among high risk occupations. Moreover, the prevalence of bovine S. japonicum infection decreased from 11.7% in 2005 to 0.6% in 2012 (P<0.001). In addition, all the 16 villages achieved the national criteria of infection control in 2008.
Our findings indicate that the integrated strategy was likely effective in controlling the transmission of S. japonicum in marshland regions in China.
PLoS ONE 02/2014; 9(2):e89779. DOI:10.1371/journal.pone.0089779 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To explore the potential key risk factors of schistosomiasis transmission in potential endemic areas so as to provide the evidence for setting up the prediction and surveillance systems of schistosomiasis outbreak epidemic.
From 2008 to 2012, fixed and mobile surveillance sites in potential endemic areas of 2 counties in Hubei Province were selected. The immunological assays and stool examinations were carried out to investigate the schistosome infection situation of local people, mobile population and livestock. The distribution of Oncomelania hupensis snails was investigated in risk areas and suspicious areas, and spreading patterns of snails were observed in the rivers that directly connected with the Yangtze River.
A total of 6 052 local people aged 6-65 years were screened by IHA immunological tests, and the positive rate of antibody was 1.19% (72/6 052). Totally 72 antibody positives were examined by Kato-Katz technique and there were no positives. A total of 5 004 mobile persons were tested by IHA immunological tests and the positive rate was 1.36% (68/5 004). Totally 68 antibody positives were examined by Kato-Katz technique and there were no positives. Totally 287.07 hm2 potential endemic areas were investigated for Oncomelania snail detection, and no snails were found. The investigation on snail spreading patterns and the surveillance on suspicious circumstances were carried out, with no snails found.
In the schistosomiasis potential endemic areas, some positives of IHA immunological tests are found. Therefore, monitoring is still needed to be strengthened.
Chinese Journal of Schistosomiasis Control 02/2014; 26(1):56-8.
[Show abstract][Hide abstract] ABSTRACT: To establish the measures of schistosomiasis field survey and evaluate the efficacy of their application according to the content of indexes of rapid assessment system to high transmission risks in schistosomiasis endemic areas of lake regions.
In 2012, based on the analysis of Oncomelania hupensis snail situation, and schistosomiasis epidemic data of human and cattle from 2008-2010, 60 villages from Hunan, Hubei, Jiangxi and Anhui provinces were selected and investigated, and the content of the investigation included the field feces, snail status, and epidemic situation of human and cattle. The systemic sampling was applied for snail investigation; the feces collected from snail investigation field were examined by the hatching test (3 bottles for 1 sample). A cluster random sampling was carried out with more than 300 people in each village. By using the hatching test (3 bottles for 1 sample) , the human stool examination was carried out for the identification of the infected persons who were positive in the immunity test screening. The hatching test was applied for cattle of all the villages (3 bottles for 1 sample).
A total of 65 field feces spots were surveyed in 60 villages, field feces were found in 78.46% (51/65) of spots, and the positive rate of field feces was 1.07% (9/842). There were 73.33% (44,160)of villages with cattle, and the largest amount cattle with 329 was found in Wufeng Village, Jiangxi Province. The cattle infection rate was 1.5 1% (4,913,242) in 3242 investigated cattle. The highest cattle infection rate was 4% in Tongxin Village, Jiangxi Province. The population of 47 099 was surveyed, the infection rate was 0.77% (364/47 099), and the highest was 4.37% in Xumuchang Village, Hunan Province. The infection rate was 0 in 43.33% (26/60) of villages. No acute schistosomiasis cases were reported in all the villages in 2011 and 2012. Totally, 77 snail spots in 60 villages were investigated, and 51 spots were marshland and 26 spots were ditches. The schistosome-infected snails were detected in 5.88% (3/51 )of the marshland spots and the living snails were found in 80.39%(41/51) of the spots. The highest density of living snails was 3.20/0.1 m2 in Xumuchang Village, Hunan Province. The average density of infected snails was 0.00045/0.1 m2 (4/8942). The infected snail spots were distributed in Liujiadi Village and Liuhe Village of Hubei Province, and Jiangkou Village of Anhui Province. No infected snails were detected in 26 ditches spots. The living snails were detected in 53.85% (14/26) of the ditches spots. The highest average density of living snails was 3.76/0.1 m2 in Huakou Village, Hubei Province.
The measures of field survey for rapid assessment system of high transmission risks in schistosomiasis endemic areas of lake regions are established and applied with scientific, impersonal and rapid characteristics.
Chinese Journal of Schistosomiasis Control 10/2013; 25(5):451-6.
[Show abstract][Hide abstract] ABSTRACT: To evaluate the effect of comprehensive measures with an emphasis on schistosomiasis infection source control by replacing cattle with machine.
In 2011, 2 villages from each of Jingzhou District, Jianli County and Jiangling County, Hubei Province, were selected as intervention group where the comprehensive measures were implemented, while 2 villages from Shishou City served as control with routine control activities. A cluster random sampling was carried out in the 8 villages with more than 300 people in each village were sampled. Stool examination using modified Kato-Katz was applied for identification of the infected persons and hatching test for cattle survey. The systemic sampling was applied for snail survey, fecal specimens from the field were examined by hatching test. Each sample was examined three times. Data were collected for the analysis of control effect between intervention and control groups in 2007 (baseline), 2009 (before implemention of comprehensive measures) and 2011 (post-intervention).
In intervention villages, the overall prevalence in human reduced significantly from 3.6% (135/3 772) in 2007 and 2.0% (63/3 116) in 2009 to 0.9% (21/2 396) in 2011 (chi2 = 43.411, chi2 = 11.840, P < 0.05). Until 2011, there were no cattle in intervention group; the prevalence decreased by 52.6% in huamn and about 100% in cattle from 2010 to 2011. In control group, the infection rate in residents in 2007, 2009 and 2011 was 4.5% (64/1 410), 2.6% (34/1 294) and 1.8% (24/1,320), respectively (chi2 = 16.178, P < 0.05), and 5.1% (8/158) in 2007, 1.6% (3/187) in 2009 and 1.6% (3/189) in 2011 in cattle, respectively (chi2 = 3.387, P > 0.05). The infection rate in human and cattle fell by 25.0% and 5.9% from 2010 to 2011, respectively. There was a significant difference in human infection rate between the intervention and control groups after intervention (chi2 = 6.309, P < 0.05). No infected snails were detected in intervention and control groups. No positive feces from the field was found in the intervention group, 7.5% positive rate was recorded in the control.
The comprehensive measures focused on infection source control by replacing cattle with machine can effectively control Schistosoma japonicum transmission, with a siginificant decrease of the prevalence in human and cattle.
Zhongguo ji sheng chong xue yu ji sheng chong bing za zhi = Chinese journal of parasitology & parasitic diseases 06/2013; 31(3):206-11.
[Show abstract][Hide abstract] ABSTRACT: Background
The transmission of schistosomiasis japonica in a local setting is still poorly understood in the lake regions of the People's Republic of China (P. R. China), and its transmission patterns are closely related to human, social and economic factors.
We aimed to apply the integrated approach of artificial neural network (ANN) and logistic regression model in assessment of transmission risks of Schistosoma japonicum with epidemiological data collected from 2339 villagers from 1247 households in six villages of Jiangling County, P.R. China. By using the back-propagation (BP) of the ANN model, 16 factors out of 27 factors were screened, and the top five factors ranked by the absolute value of mean impact value (MIV) were mainly related to human behavior, i.e. integration of water contact history and infection history, family with past infection, history of water contact, infection history, and infection times. The top five factors screened by the logistic regression model were mainly related to the social economics, i.e. village level, economic conditions of family, age group, education level, and infection times. The risk of human infection with S. japonicum is higher in the population who are at age 15 or younger, or with lower education, or with the higher infection rate of the village, or with poor family, and in the population with more than one time to be infected.
Both BP artificial neural network and logistic regression model established in a small scale suggested that individual behavior and socioeconomic status are the most important risk factors in the transmission of schistosomiasis japonica. It was reviewed that the young population (≤15) in higher-risk areas was the main target to be intervened for the disease transmission control.
[Show abstract][Hide abstract] ABSTRACT: Schistosomiasis is one of the major public health problems in the People's Republic of China (and elsewhere), seriously threatening health as well as social and economic development. An integrated control strategy, emphasising transmission control but also aimed at reducing greenhouse gases, was carried out in Jiangling county, Hubei province from 2007 to 2009. Three villages were chosen for a pilot study involving removal of cattle from neighbouring, snail-infested grasslands, improving sanitation and construction of units for household biogas production in addition to routine control measures. Both prevalence and intensity of infection in the snails in the neighbourhood were greatly reduced after two years of implementation, while the prevalence of schistosomiasis in humans in the three villages had been reduced by 29%, 34% and 24%, respectively. The removal of cattle and construction of biogas production units had an additional positive effect in that the annual, average emission of greenhouse gases such as methane (CH4) and carbon dioxide (CO2) were reduced by an estimated 7.8 and 80.2 tons, respectively.
Geospatial health 05/2012; 6(2):215-20. DOI:10.4081/gh.2012.139 · 1.19 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To investigate the schistosome infectivity of the water body of the Yangtze River and Hanbeihe River during flooding in Hubei Province.
The Oncomelania snail status was investigated in 17 sites of the Yangtze River and Hanbei River, and the infectivity of schistosome in sentinel mice was also determined.
In the Yangtze River and Hanbei River, the average densities of living snails were 0.35 snails/0.1 m2 and 0.67 snails/0.1 m2 respectively, and the average infection rates of snails were 0.33% and 0.05%, respectively. The sentinel mouse surveillances were carried out twice in 10 sites of the Yangtze River. During the first surveillance the infection rate was 5.5% with 4 positive environment sites, and that was 5.5% with 7 positive environment sites in the second surveillance. The sentinel mouse surveillance was carried out once in 7 sites of the Hanbeihe River, and the infection rate was 11.9% with 4 positive environment sites.
By monitoring schistosome infection of the water body, we can understand the threat of environment and provide warning information to prevent from the outbreak and spread of acute schistosomiasis. We can also indirectly get many messages about the quality of snail investigation and the effect of mollusciciding.
Chinese Journal of Schistosomiasis Control 04/2012; 24(2):193-5, 199.
[Show abstract][Hide abstract] ABSTRACT: Appropriate diagnostics to monitor disease trends and assess the effectiveness and impact of interventions are essential for guiding treatment strategies at different thresholds of schistosomiasis transmission and for certifying elimination. Field validation of these assays is urgently needed before they can be adopted to support policy decisions of the national programme for control and elimination of schistosomiasis in P.R. China. We compared the efficacy and utility of different immunoassays in guiding control strategies and monitoring the endemic status of S. japonicum infections towards elimination.
A cross-sectional survey was conducted in seven villages with different transmission intensities settings to assess the performance and utility of three immunoassays, e.g., an indirect hemagglutination assay (IHA_JX), an enzyme linked immunosorbent assay (ELISA_SZ), and a dot immunogold filtration assay (DIGFA_SH). 6,248 individuals aged 6-65 years old who gave consent and supplied their stool and blood samples were included for data analysis. Results showed that ELISA_SZ performed significantly higher sensitivity (95.45%, 95%CI: 92.94-97.97%) than IHA_JX (87.59%, 95%CI: 83.51-91.49%) and DIGFA_SH (79.55%, 95%CI: 74.68-84.41%), especially in subgroups with very low infection intensity. The specificity of ELISA_SZ, IHA_JX, DIGFA_SH in 6-9 year olds with occasional exposure was nearly 90%. DIGFA_SH performed the highest screening efficacy for patients among three assays with overall positive predicative value of 13.07% (95%CI: 11.42-14.72%). We found a positive correlation of antibody positive rate of IHA_JX with results of stool examination in age strata (r = 0.70, P<0.001). Seropositivity of IHA_JX in children aged 6-9 years old showed an excellent correlation with prevalence of schistosome infection in the seven communities (r = 0.77, P<0.05).
Studies suggest that ELISA_SZ could be used to guide selective chemotherapy in moderate or low endemic regions. IHA_JX could be used to as a surveillance tool and for certifying elimination of schistosomiasis through monitoring children as a sentinel population.
[Show abstract][Hide abstract] ABSTRACT: The status of schistosomiasis transmission control in Hongshan District of Wuhan City was evaluated. The schistosome infection rates of human and cattle were both below 1%, no local acute schistosomiasis patient occurred, and infected snails were not found during the period of 2008 to 2010. The files and data were well-documented. Therefore, Hongshan District reached the national criteria for schistosomiasis transmission control.
Chinese Journal of Schistosomiasis Control 06/2011; 23(3):257, 261.
[Show abstract][Hide abstract] ABSTRACT: This paper reviewed the current endemic features and situation of schistosomiasis in lake and marshland regions in China, and discussed the comprehensive control strategy for schistosomiasis with emphasis on infectious sources control, including its theoretical basis, the reality conditions of implementation and technical composition, and also introduced the effectiveness of the pilot trails and their large-scale application as well as several issues in the implementation. The aim of the review is to accelerate the process of schistosomiasis control in lake and marshland regions and promote the achievement of mid- and long-term goals in national schistosomiasis control program.
Chinese Journal of Schistosomiasis Control 02/2011; 23(1):5-9.